1. Field of the Invention
The present invention is generally in the field of electrical circuits. More particularly, the invention is in the field of driver circuits for powering loads.
2. Background Art
Applications, such as lighting applications, can require a load, such as a load including one or more light-emitting diodes (LEDs), to be powered off-line, i.e., from an AC power source, such as an AC line. To power a load, such as an LED load, from an AC line, the AC line voltage is typically converted into a rectified DC voltage via a full-bridge rectifier. The rectified DC voltage can then be appropriately filtered to provide a substantially constant DC voltage, which can be converter to an appropriate voltage level as required by the load, such as an LED load. However, conventional solutions for powering a load, such as a load including one or more LEDs, from an AC line (i.e. off-line) can suffer from various drawbacks.
One conventional solution for powering a load, such as a load including one or more LEDs, off-line utilizes a flyback circuit. However, flyback circuits typically have an efficiency of only 80.0 to 85.0 percent and a maximum power limitation of approximately 50.0 watts, which are undesirable features. Another conventional solution utilizes a buck converter to provide the necessary DC voltage required for a load, such as an LED load. However, the buck converter generally has an undesirably low power factor. Additionally, the aforementioned conventional solutions typically require a large filter capacitor, such as a large electrolytic capacitor, which can undesirably increase cost.